For my Java Swing app I want to display a grid of items, fixed to two columns, and for the elements (grid items), I want to use fixed height, and if due to its height they don't fit, place a vertical scrollbar.
For anyone who knows a bit about Android development, is more or less what GridView does perfectly.
So, I'm trying to find a way to do that. I tried with a JPanel with GridLayout inside a JScrollPane, but in this case the elements get too much width and I also need a horizontal scrollbar, which definitely is not what I want.
So, what do you suggest?
Thank you.
Related
What I want is a little unusual. I want to make a screen that shows me a number squares inside of it. I should be able to determine the number of rows and lines by two integers. I also want to be able to set for example colors of the squares, and they should be clickable so they need to have an id that is numbered and an onClick function.
For example:
height=2
rows=3
color1=FFFFFF
color5=000000
is Something like this achievable? How should I approach this?
I think what you're looking for is a JButton.
For your particular problem, consider creating a 2D Array of JButtons and display them using a JPanel and JFrame. The size height and width of your grid would be the length of each of these arrays. E.g.
myArray.length() is the width (number of columns in the grid) and myArray[0].length() is the height of the grid (number of rows).
JButton supports setting images and colours.
Documentation:
https://docs.oracle.com/javase/tutorial/uiswing/components/button.html
I have made a program that uses null, border, card and some my custom layouts. The window of the program is set to resizable:false. Now I wan't to make full screen mode for my program but the problem is that GUI looks ugly if the size of the screen isn't the one I set. I could implement some kind of scale factor for all the components but the problem is that I have over 2000 components in over 50 classes.
Is there an option to resize whole swing UI for defined factor? That means that the image rendered as UI and all mouse events aswell would be resized.
You should probably try to rely on your layout managers. Try to figure out specifically which layouts aren't resizing the way you want, and focus on correcting their behavior instead of trying to manage everything from the top down.
Alternatively, you could keep the size ratio by adding black bars to the top and bottom or left and right of the window when it's in full screen mode. You'll probably still have to play with some of the layouts to get them perfect though.
Having 2000 different components sounds like a usability nightmare, but that's a different issue.
This doesn't seem like it should be very hard but I can't figure out how to do this:
I have a subclass of JPanel. It has a fixed height, but can be any width. The subclasses, on construction, set their preferred size using setPreferredSize(), which means I have to provide a width in addition to the height.
I would like to make a scrolling list of some number of my subclass, where the subclasses all fill the available horizontal space.
Right now I have a scroll view containing a JPanel containing my subclasses. The containing JPanel uses a BoxLayout with a vertical orientation.
Vertically, it looks great. Horizontally, my custom panels are just stuck at the preferred size. What would be the easiest way to make my panels fill the available horizontal space? I tried writing some layout listeners for them, but the performance was flakey (it seems that sometimes the event messages get dropped?) and the code looked hacky. Other views, such as the JList, JTree, and scroll views seem to resize automatically to fill the available space in a BoxLayout, so I feel like there must be something I can do in my JPanel subclass that I haven't thought of.
I'm open to using another Layout Manager if something else is better suited for this. I looked at GridBagLayout, but that seemed more geared towards static layouts where components aren't added and removed at runtime.
Edit: I found this on Oracle's Documentation for BoxLayout which has an example that looks exactly like what I want:
What if none of the components has a maximum width? In this case, if all the components have identical X alignment, then all components are made as wide as their container. If the X alignments are different, then any component with an X alignment of 0.0 (left) or 1.0 (right) will be smaller. All components with an intermediate X alignment (such as center) will be as wide as their container. Here are two examples:
Could someone show me the code that will produce the same results? The example code in the documentation doesn't look like it covers this particular picture.
When you put your component in a JScrollPane, your component may implement the Scrollable interface to adjust the scrollpane’s behaviour. By doing this you can implement the method getScrollableTracksViewportWidth() to return true so your component will always have the available width and be scrollable in vertical direction only.
This is how JList, JTable, JTree, and all the text components of Swing do it.
Alright - I found the problem. It appears that the default implementation of getMinimumSize() and getMaximumSize() will simply return the value of getPreferredSize() if it is set. So by setting a preferred size without a maximum size, my maximum size was the preferred size. By overriding getMaximumSize() to return (99999, preferredHeight), it now works exactly as I want.
Give that I have written a JPanel with many different components on it, is there a way to apply an overall "dilate" ability on the panel so that everything in it stretches proportionally when I resize my window?
That is, if I manually resize my window to be 1/4 the size, everything in the panel should also shrink by 1/4 so the new panel is just a dilation of the first. Given that I have not designed the individual components inside to do this (there are many) is there any easy way to make the panel behave this way?
UPDATE: In order to be more clear on the solution I need, I will describe the panel contents:
The panel is a "game" of sorts, with a single null-layout and dozens of ImageIcons flying around the screen at any time. The ImageIcons are preloaded PNG files, which already have a permanent size. Of course, I could manually resize each ImageIcon and reposition them relative to window size, but that would involve recoding many components.
There are no buttons or text to worry about, so what I'm really looking for is some kind of "postprocessed" resize where the panel simply shrinks whatever's rendered by some porportion (think of resizing an image in Photoshop).
One option is of course to give up swing all together and use some 3rd party widget component library which draws itself using any Graphics. Then you can either draw the widgets on the image and resize the image, or, better yet, apply a transform to the graphics object you pass to the library.
If you do want to stick with swing there is the SwingUtilities.paintComponent method, which you could use to paint the Panel onto a BufferedImage which you could then resize. (I've used this myself to do some nice transitions between "views" in a game.)
The problem is of course that you somehow need to translate the user input accordingly. I have no solution for this right now, but the above perhaps helps you in some way.
You can try to override paintChildren() method of the panel and scale graphics to achieve desired visible size.
You could try J(X)Layer, see http://www.pbjar.org/blogs/jxlayer/jxlayer40/
Using layout managers instead of absolute positioning of the widgets will give you this behaviour. See the oracle tutorials: Using Layout Managers.
Do you really want fonts to resize on resize events? I don't know a layout manager which will do that for you.
I was thinking of doing a commodore 64 style loading screen (with the alternating bars that change colour and grow/shrink in size) and was wondering if anyone has tried this or knows of any code I could look at. I'm gonna make a start on it myself today, but it would be good to have something to compare it against :)
So far, I'm guessing you divide the screen size up and set a constant for the bar height (say 12 horizontal bars for example) and you pick a random number between the constant and constant - 5 or whatever and refresh the screen. It's hard to tell looking at it, but it's something I'd be interested in reproducing.
I'd override paintComponent() to draw the horizontal bars. To tile the overlay, you might look at this example that uses getSubimage() to slice the image and javax.swing.Timer to pace the animation.
Addendum: See also this example that does horizontal slices.